Edgetech 4125I User manual

EdgeTech
4 Little Brook Road
West Wareham, MA 02576
Tel: [phone]
Fax: [phone]
www.EdgeTech.com
4125I/4125 SIDE SCAN SONAR SYSTEM
USER HARDWARE MANUAL
0004823_REV_G August 2020

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4125i/4125 SIDE SCAN SONAR SYSTEM 0004823_REV_G
The information, figures, and specifications in this manual are proprietary. They are issued in strict
confidence on condition that they not be copied, reprinted, or disclosed to a third party, either wholly or
in part, without the prior written consent of EdgeTech. Any reproduction of EdgeTech supplied software
or file sharing is strictly prohibited.
EdgeTech © 2016-2020. All rights reserved.
Microsoft® and Windows® are registered trademarks of Microsoft Corporation.
Kevlar® is a registered trademark of the DuPont Company.
Intel® and Pentium® are registered trademarks of Intel Corporation.
Novagard G624® is a trademark of Novagard Solutions, Inc.
Storm Case™ is a trademark of Pelican, Inc.
CentrinoTM is a trademark of Intel Corporation.
Kellems® is a registered trademark of Hubbell Incorporated.

iii
ATTENTION – READ THIS FIRST!
All personnel involved with the installation, operation, or maintenance of the equipment described in this
manual should read and understand the warnings and cautions provided below.
CAUTION!This equipment contains devices that are extremely sensitive
to static electricity. Therefore, extreme care should be taken when
handling them. Normal handling precautions involve the use of anti-static
protection materials and grounding straps for personnel.
WARNING!High Voltage may be present in all parts of the system.
Therefore, use caution when the electronics are removed from their
containers for servicing.
CAUTION!Operation with improper line voltage may cause serious
damage to the equipment. Always ensure that the proper line voltage is
used.

iv
4125i/4125 SIDE SCAN SONAR SYSTEM 0004823_REV_G
HARDWARE VARIATIONS AND COMPATIBILITY
4125 Series Side Scan Sonar Systems contain both standard and proprietary hardware. The 4125i and the
4125 SAR Side Scan Sonar Systems are the current standard hardware configurations. The 4125 (no i) is a
legacy system that was replaced by the 4125i. Each variant in the series has its own set of options.
The 4125i is an improved version of the legacy 4125 system that replaces the obsolete xDSL towfish and
topside modems in the system. 4125i and 4125 towfish and topside equipment are not compatible with
one another as the chipset used in the obsolete 4125 xDSL modems are not compatible with the new
modems used in the 4125i. Both topside and towfish must be purchased or upgraded to the 4125i
standard to interface correctly. Contact EdgeTech CUSTOMER SERVICE for details and assistance on any
upgrade. Full system documentation on this system can be found in this manual and the 4125 SOFTWARE
MANUAL (0016652).
The 4125 SAR Side Scan Sonar System is a variant with configurations and options that are optimized for
search and recovery surveys. These configurations and options may make the 4125 SAR towfish and
portable topside not compatible with non-SAR 4125 system components. Contact EdgeTech CUSTOMER
SERVICE for details and assistance if this is the case. Full system documentation can be found in the 4125-
SAR HARDWARE MANUAL (0019251) and 4125 SOFTWARE MANUAL (0016652).
EdgeTech may change the standard components due to their availability or performance improvements.
Although the component manufacturers—along with their models and styles—may change from unit to
unit, replacement parts will generally be interchangeable.
EdgeTech will make every effort to see that replacement components are interchangeable and use the
same software drivers (if applicable). At times, however, direct replacements may not exist. When this
happens, EdgeTech will provide the necessary drivers with the replacement part, if applicable.
EdgeTech may also change specific hardware per customer requirements. Therefore, portions of this
manual, such as parts lists and test features, are subject to change. These sections should be used for
reference only. When changes are made that affect system operation, they will be explicitly noted. Also,
some options and features may not be active in the customer’s unit at the time of delivery. Upgrades will
be made available when these features are implemented.
Contact CUSTOMER SERVICE with any questions relating to compatibility.

v
ABOUT THIS DOCUMENT
We, the employees at EdgeTech, would like to thank you for purchasing the 4125i Side Scan Sonar System.
At EdgeTech, it is our policy to provide high-quality, cost-effective products and support services that meet
or exceed your requirements. We also strive to deliver them on-time and to look for ways to improve
them continuously. We take pride in the products we manufacture and want you to be entirely satisfied
with your equipment.
Purpose of this Manual
The purpose of this manual is to provide the user with information on the setup and use of EdgeTech’s
4125 and 4125i systems. The 4125 SAR variant is documented in the 4125-SAR HARDWARE MANUAL
(0019251). Although this manual encompasses the latest operational features of each, some features may
be periodically upgraded. Therefore, the information in this manual is subject to change and should be
used for reference only.
Liability
EdgeTech has made every effort to document the 4125 and 4125i in this manual accurately and
completely. However, EdgeTech assumes no liability for errors or for any damages that result from the
use of this manual or the equipment it documents. EdgeTech reserves the right to upgrade the features
of this equipment, and to make changes to this manual, without notice at any time.
Warnings, Cautions, and Notes
Where applicable, warnings, cautions, and notes are provided in this manual as follows:
WARNING! Identifies a potential hazard that could cause injury or death.
CAUTION! Identifies a potential hazard that could damage equipment or
data.

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4125i/4125 SIDE SCAN SONAR SYSTEM 0004823_REV_G
NOTE: Recommendations or general information that is particular to the
material being presented.
Revision History
REVISION
DESCRIPTION
DATE
APPROVAL
B Update specifications 01/02/2011 RM
C Updated formatting/specs 01/21/2014 RM
D Updated specifications 05/03/2016 RM
E
Updated for new tail cone
and vertical scanability
07/07/2016 TS
F
Updated specifications and
drawings
10/28/2016 TS
G
Added 4125 Info, Specs, and
Drawings. Pictures, Tables,
and Formatting updated.
08/19/2020 PO

vii
WARRANTY STATEMENT
All equipment manufactured by EdgeTech is warranted against defective components and workmanship
for a period of one year after shipment. Warranty repair will be done by EdgeTech free of charge.
Shipping costs are to be borne by the customer. Malfunction due to improper use is not covered in the
warranty, and EdgeTech disclaims any liability for consequential damage resulting from defects in the
performance of the equipment. No product is warranted as being fit for a particular purpose, and there is
no warranty of merchantability. This warranty applies only if:
i. The items are used solely under the operating conditions and in the manner recommended in
Seller’s instruction manual, specifications, or other literature.
ii. The items have not been misused or abused in any manner, nor have repairs been attempted
thereon without the approval of EdgeTech Customer Service.
iii. Written notice of the failure within the warranty period is forwarded to Seller, and the directions
received for properly identifying items returned under warranty are followed.
iv. The return notice authorizes Seller to examine and disassemble returned products to the extent
Seller deems necessary to ascertain the cause for failure.
The warranties expressed herein are exclusive. There are no other warranties, either expressed or implied,
beyond those set forth herein, and Seller does not assume any other obligation or liability in connection
with the sale or use of said products. Any product or service repaired under this warranty shall be
warranted for the remaining portion of the original warranty period only.
Equipment not manufactured by EdgeTech is supported only to the extent of the original manufacturer’s
warranties.
CAUTION! If your product is a portable topside, never attempt to ship it
in its Storm CaseTM alone. Shipping portable topsides without an exterior
shipping crate will void the warranty.

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4125i/4125 SIDE SCAN SONAR SYSTEM 0004823_REV_G
SOFTWARE SERVICE OVERVIEW
EdgeTech provides software services free of charge. This software agreement does not address customer-
specified modifications or enhancements. These services may be ordered separately. Furthermore,
EdgeTech software upgrades are meant for the sole use of EdgeTech customers. Any reproduction of
EdgeTech-supplied software or file sharing is strictly prohibited.
Software Updates and Enhancements
EdgeTech customers can download new software releases with all modifications and enhancements from
the EdgeTech FTP site that can be accessed by contacting EDGETECH CUSTOMER SERVICE.Major software
issues, should they occur, will be reported directly to the customer. New software releases consist of the
following:
•Software enhancements that are not on the price list
•Software fixes and changes
•Product integration
•Documentation updates to on-line help
•Tests for compatibility with other modules
Software patches consist of software that has undergone the following:
•Minor software enhancements
•Software fixes and changes
•Software Telephone, Facsimile, and E-mail Support
EdgeTech customers are entitled to contact EDGETECH CUSTOMER SERVICE by telephone, facsimile, or e-mail
to report a difficulty, to discuss a problem, or to receive advice on the best way to perform a task. When
contacted, EdgeTech Customer Service will do the following:
•Respond within 24 hours
•Immediately attend to serious problems affecting operations
•Attempt to find an immediate workaround

ix
RETURNED MATERIAL AUTHORIZATION
Before returning any equipment to EdgeTech, a Returned Material Authorization (RMA) number must be
obtained. The RMA will help us identify your equipment when it arrives at our receiving dock and track
the equipment while it is at our facility. The material should be shipped to the address provided in the
EDGETECH CUSTOMER SERVICE section. Please refer to the RMA number on all documents and
correspondences as well.
All returned materials must be shipped prepaid. Freight collect shipments will not be accepted. EdgeTech
will pay freight charges on materials going back to the customer after they have been evaluated and/or
repaired.
CAUTION! If your product is a portable topside, never attempt to ship it
in its Storm CaseTM alone. Although rugged, these cases are not intended
to be used as shipping containers, and the delicate internal components
could be damaged if used in this manner.
The following steps apply only to the material being returned from outside the Continental United States.
Follow them carefully to prevent delays and additional costs.
1. All shipments must be accompanied by three copies of your proforma invoice, showing the value
of the material and the reason for its return. If the reason is for repair, it must be clearly stated in
order to move through customs quickly and without duties being charged. Whenever possible,
please send copies of the original export shipping documents with the consignment.
2. If the value of the equipment is over $1000, the following Shipper’s oath must be sent with the
invoice. This oath can be typed on the invoice, or on a separate letterhead:
"I, ______________________________, declare that the articles herein specified are the
growth, produce, or manufacture of the United States; that they were exported from the
United States from the port of _____________________, on or about _______________;
that they are returned without having been advanced in value or improved in condition
by any process of manufacture or any other means; and that no drawback, or allowance
has been paid or admitted hereof."
Signed ______________________________

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4125i/4125 SIDE SCAN SONAR SYSTEM 0004823_REV_G
3. If there is more than one item per consignment, a packing list must accompany the shipment. It
is acceptable to combine the proforma invoice and packing list if the contents of each carton are
clearly numbered and identified on the invoice.
4. Small items can be shipped prepaid directly to EdgeTech by FedEx, DHL, UPS, Airborne, etc.
5. If the equipment is the property of EdgeTech (formerly EG&G Marine Instruments Division),
please insure for full value.
6. Fax one invoice, packing list, and a copy of the airway bill to EdgeTech upon shipment.

xi
CUSTOMER SERVICE
Customer service personnel at EdgeTech are always eager to hear from users of our products. Your
feedback is welcome and is a valuable source of information which we use to continually improve these
products. Therefore, we encourage you to contact EdgeTech Customer Service to offer any suggestions
or to request technical support:
NOTE: Please have your system Model and Serial Number available when
contacting Customer Service.
E-mail: [e-mail]
Mail: 4 Little Brook Road
West Wareham, MA 02576
Telephone: [phone]
Facsimile: [phone]
24-Hour Emergency
Technical Support Line: [phone]
For more information, please go to www.EdgeTech.com.

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4125i/4125 SIDE SCAN SONAR SYSTEM 0004823_REV_G
COMPANY BACKGROUND
EdgeTech (formerly EG&G Marine Instruments) traces its history in underwater data acquisition and
processing back to 1966. EdgeTech has designed, developed, and manufactured products, instruments,
and systems—for the acquisition of underwater data, including marine, estuarine, and coastal
applications—for over 45 years.
The company has responded to the needs of the scientific, Naval, and offshore communities by providing
equipment—such as sub-bottom profilers, side scan sonar, acoustic releases, USBL positioning systems,
and bathymetric systems—that have become standards in the industry.
EdgeTech has also consistently anticipated and responded to future needs through an active research and
development program. Current efforts are focused on the application of cutting-edge CHIRP and acoustic
technology.

xiii
TABLE OF CONTENTS
ATTENTION – READ THIS FIRST! ............................................................................................................. iii
HARDWARE VARIATIONS AND COMPATIBILITY ..................................................................................... iv
ABOUT THIS DOCUMENT ........................................................................................................................ v
Purpose of this Manual........................................................................................................................ v
Liability................................................................................................................................................ v
Warnings, Cautions, and Notes............................................................................................................ v
Revision History.................................................................................................................................. vi
WARRANTY STATEMENT....................................................................................................................... vii
SOFTWARE SERVICE OVERVIEW........................................................................................................... viii
Software Updates and Enhancements ...............................................................................................viii
RETURNED MATERIAL AUTHORIZATION ................................................................................................ ix
CUSTOMER SERVICE............................................................................................................................... xi
COMPANY BACKGROUND..................................................................................................................... xii
TABLE OF CONTENTS............................................................................................................................ xiii
LIST OF FIGURES................................................................................................................................. xviii
LIST OF TABLES...................................................................................................................................... xx
1.0 OVERVIEW..................................................................................................................................1-1
1.1 4125 Series Applications .......................................................................................................1-1
1.2 Main System Components ....................................................................................................1-1
1.2.1 Towfish ............................................................................................................................1-1
1.2.2 4125i-P Topside Processor ...............................................................................................1-3
1.2.3 4125i-RM Topside Processor ............................................................................................1-4
1.2.4 Tow Cable ........................................................................................................................1-4
1.2.5 Optional Equipment.........................................................................................................1-5
1.2.5.1 Depressor Wing........................................................................................................1-5
1.2.5.2 Keel Weight..............................................................................................................1-6
1.2.5.3 HullScan Kit..............................................................................................................1-6
2.0 SPECIFICATIONS .........................................................................................................................2-7
2.1 4125i Topside Processor Specifications .................................................................................2-7
2.1.1 4125i Topside Diagrams and Drawings .............................................................................2-8

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4125i/4125 SIDE SCAN SONAR SYSTEM 0004823_REV_G
2.2 4125i Towfish Specifications ...............................................................................................2-13
2.2.1 4125i Towfish Drawings .................................................................................................2-14
2.3 Cable Drawings...................................................................................................................2-18
3.0 SETUP AND ACTIVATION ..........................................................................................................3-23
3.1 Unpacking and Inspection...................................................................................................3-23
3.2 Power Requirements ..........................................................................................................3-23
3.2.1 Use of an Uninterrupted Power Supply ..........................................................................3-24
3.2.2 Changing a Non-US Power Plug ......................................................................................3-24
3.3 Navigation Interface ...........................................................................................................3-24
3.4 Placement of the Topside Processor ...................................................................................3-24
3.4.1 4125i-P Topside Processor Placement ............................................................................3-25
3.4.2 4125i Rack Mount Topside Processor .............................................................................3-25
3.5 Topside Controls and Indicators..........................................................................................3-25
3.5.1 4125i-P Topside Processor Controls and Indicators.........................................................3-25
3.5.2 4125i Rack Mount Topside Controls and Indicators ........................................................3-27
3.6 Topside Processor Connections...........................................................................................3-29
3.6.1 4125i-P Topside Processor Connections .........................................................................3-29
3.6.2 4125i Rack Mount Topside Processor Connections .........................................................3-29
3.7 TCP/IP Address Settings ......................................................................................................3-29
3.8 Assembling the 4125i Towfish.............................................................................................3-30
3.9 Installing Optional Equipment.............................................................................................3-30
3.9.1 Installing the Hull Scan Kit ..............................................................................................3-31
3.9.2 Installing the Depressor Wing.........................................................................................3-33
3.10 Connecting the System Components...................................................................................3-36
3.10.1 Connecting and Attaching the Tow Cable to the Towfish................................................3-36
3.10.2 Connecting the Topside..................................................................................................3-38
3.10.2.1 Connecting the 4125i-P Topside Processor .............................................................3-38
3.10.2.2 Connecting the 4125i-RM Rack Mount Topside ......................................................3-38
3.11 System Activation and Test .................................................................................................3-39
3.11.1 Preparing a Wired Ethernet LAN Connection..................................................................3-39
3.11.2 Preparing a Wireless Ethernet LAN Connection (4125i-P Only) .......................................3-39
3.11.3 Activating the 4125i Series System .................................................................................3-40

xv
3.12 Performing Pre-deployment Checks....................................................................................3-40
3.13 Towfish Deployment...........................................................................................................3-42
3.14 Towing Characteristics........................................................................................................3-45
3.14.1 4125i Towfish Cable Layback Plots .................................................................................3-45
3.14.1.1 Config. 2: 4125i, 23080 Cable - 100m Long .............................................................3-51
3.14.1.2 Config. 4: 4125i, 23080 Cable - 300m Long .............................................................3-52
3.14.1.3 Config. 6: 4125i + 15 lb. Keel Weight, 23080 Cable - 100m Long .............................3-53
3.14.1.4 Config. 8: 4125i + 15 lb. Keel Weight, 23080 Cable - 300m Long .............................3-54
3.14.1.5 Config. 10: 4125i + Depressor Wing, 23080 Cable - 100m Long ...............................3-55
3.14.1.6 Config. 12: 4125i + Depressor Wing, 23080 Cable - 300m Long ...............................3-56
3.14.1.7 Config. 14: 4125i + 15 lb. Keel Wt. + Depressor Wing, 23080 Cable – 100m ............3-57
3.14.1.8 Config. 16: 4125i + 15 lb. Keel Wt. + Depressor Wing, 23080 Cable – 300m ............3-58
3.14.1.9 Config. 18: 4125i, A304874 Cable - 100m Long .......................................................3-59
3.14.1.10 Config. 20: 4125i, A304874 Cable - 300m* Long .....................................................3-60
3.14.1.11 Config. 22: 4125i + 15 lb. Keel Weight, A304874 Cable - 100m Long .......................3-61
3.14.1.12 Config. 24: 4125i + 15 lb. Keel Weight, A304874 Cable - 300m* Long .....................3-62
3.14.1.13 Config. 26: 4125i + Depressor Wing, A304874 Cable - 100m Long...........................3-63
3.14.1.14 Config. 28: 4125i + Depressor Wing, A304874 Cable - 300m* Long.........................3-64
3.14.1.15 Config. 30: 4125i + 15 lb. Keel Wt. + Dep. Wing, A304874 Cable - 100m .................3-65
3.14.1.16 Config. 32: 4125i + 15 lb. Keel Weight + Dep. Wing, A304874 Cable - 300m*..........3-66
3.14.1.17 Config. 34: 4125i, A320327 Cable - 100m Long .......................................................3-67
3.14.1.18 Config. 37: 4125i, A320327 Cable - 400m Long .......................................................3-68
3.14.1.19 Config. 39: 4125i + 15 lb. Keel Weight, A320327 Cable - 100m Long .......................3-69
3.14.1.20 Config. 42: 4125i + 15 lb. Keel Weight, A320327 Cable - 400m Long .......................3-70
3.14.1.21 Config. 44: 4125i + Depressor Wing, A320327 Cable - 100m Long...........................3-71
3.14.1.22 Config. 47: 4125i + Depressor Wing, A320327 Cable - 400m Long...........................3-72
3.14.1.23 Config. 49: 4125i + 15 lb. Keel Wt. + Dep. Wing, A320327 Cable – 100m.................3-73
3.14.1.24 Config. 52: 4125i + 15 lb. Keel Wt. + Dep. Wing, A320327 Cable - 400m .................3-74
3.14.1.25 Config. 54: 4125i, A302799 Cable - 100m Long .......................................................3-75
3.14.1.26 Config. 57: 4125i, A302799 Cable - 400m Long .......................................................3-76
3.14.1.27 Config. 59: 4125i, A302799 Cable - 600m Long .......................................................3-77
3.14.1.28 Config. 61: 4125i + 15 lb. Keel Weight, A302799 Cable - 100m Long .......................3-78

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4125i/4125 SIDE SCAN SONAR SYSTEM 0004823_REV_G
3.14.1.29 Config. 64: 4125i + 15 lb. Keel Weight, A302799 Cable - 400m Long .......................3-79
3.14.1.30 Config. 66: 4125i + 15 lb. Keel Weight, A302799 Cable - 600m Long .......................3-80
3.14.1.31 Config. 68: 4125i + Depressor Wing, A302799 Cable - 100m Long...........................3-81
3.14.1.32 Config. 71: 4125i + Depressor Wing, A302799 Cable - 400m Long...........................3-82
3.14.1.33 Config. 73: 4125i + Depressor Wing, A302799 Cable - 600m Long...........................3-83
3.14.1.34 Config. 75: 4125i + 15 lb. Keel Wt. + Dep. Wing, A302799 Cable – 100m.................3-84
3.14.1.35 Config. 78: 4125i + 15 lb. Keel Wt. + Dep. Wing, A302799 Cable - 400m .................3-85
3.14.1.36 Config. 80: 4125i + 15 lb. Keel Weight + Dep. Wing, A302799 Cable - 600m............3-86
3.15 Towfish Recovery................................................................................................................3-87
4.0 MAINTENANCE .........................................................................................................................4-88
4.1 Cleaning the 4125i System ..................................................................................................4-88
4.1.1 Inspecting and Cleaning the Connections .......................................................................4-88
4.2 Rearming the Towfish.........................................................................................................4-89
5.0 TROUBLESHOOTING .................................................................................................................5-90
5.1 Restoring the Operating System to the Hard Drive..............................................................5-90
5.2 Disassembling and Reassembling the Towfish.....................................................................5-90
5.2.1 Disassembly ...................................................................................................................5-90
5.2.2 Reassembly....................................................................................................................5-94
5.3 Calibrating the Compass .....................................................................................................5-94
5.3.1 Changing the Angle of Declination................................................................................5-102
5.4 General Troubleshooting ..................................................................................................5-106
5.5 4125i-P Topside Processor Troubleshooting......................................................................5-107
5.6 4125i Towfish Troubleshooting .........................................................................................5-107
5.7 Tow Cable Inspection........................................................................................................5-110
5.7.1 Locating a Shorted Conductor ...................................................................................... 5-110
5.7.2 Locating an Open Conductor ........................................................................................5-111
5.7.3 Locating a Resistance Breakdown................................................................................. 5-111
5.7.4 Damaged Tow Cable Connector ...................................................................................5-111
5.8 SYSTEM RESTORE..............................................................................................................5-112
5.9 PRINTERS..........................................................................................................................5-113
5.10 4125i AND 4125 SPARE KITS..............................................................................................5-114

xviii
4125i/4125 SIDE SCAN SONAR SYSTEM 0004823_REV_G
LIST OF FIGURES
Figure 1-1: 4125 Towfish ......................................................................................................................1-3
Figure 1-2: 4125 Laptop and Portable Topside Processor ......................................................................1-4
Figure 1-3: Tow Cable ...........................................................................................................................1-5
Figure 1-4: Optional Depressor Wing ....................................................................................................1-6
Figure 1-5: Optional Inverted HullScan Bracket.....................................................................................1-6
Figure 2-1: 4125i Series Block Diagram (Wireless for Portable Topside Only) ........................................2-9
Figure 2-2: 4125i-P Case ICD Drawing .................................................................................................2-10
Figure 2-3: 4125i-RM Topside Processor .............................................................................................2-11
Figure 2-4: 4125i-RM Topside Processor with Hobbs Meter................................................................2-12
Figure 2-5: 4125i with Depressor Wing ICD Drawing ...........................................................................2-15
Figure 2-6: 0010482, DOC Drawing ICD SS Array 4125.........................................................................2-16
Figure 2-7 4125 Electronics Bottle ......................................................................................................2-17
Figure 2-8: Kevlar Reinforced Tow Cable, Telemetry...........................................................................2-19
Figure 2-9: AC Power Cable.................................................................................................................2-20
Figure 2-10: DC Power Cable for Portable Topside ..............................................................................2-21
Figure 2-11: Ethernet Cable ................................................................................................................2-22
Figure 3-1: 4125-P Topside Processor Side Panel ................................................................................3-26
Figure 3-2: 4125i Rack Mount Front Panel—Controls and Indicators...................................................3-28
Figure 3-3: 4125i Rack Mount Back Panel—Controls and Connections ................................................3-28
Figure 3-4: Tail Assembly Drawing ......................................................................................................3-30
Figure 3-5: Horizontal (Inverted) Hull-Scan Bracket Attached..............................................................3-31
Figure 3-6: Vertical Hull-Scan Bracket Attached ..................................................................................3-32
Figure 3-7: Connected Towfish (Horizontal Hull-Scan Shown) .............................................................3-33
Figure 3-8: Depressor Wing bracket shown attached to tow fish bracket ............................................3-34
Figure 3-9: Depressor Wing Recovery Cable Attached to Towfish Rear Handle....................................3-34
Figure 3-10: Tow cable shown Routed through Depressor Wing Top Hole...........................................3-35
Figure 3-11: Tow cable and Tow Fish Pigtail Connectors. ....................................................................3-35
Figure 3-12: Cable grip attached to Depressor Wing Mounting Point. .................................................3-36
Figure 3-13: Towfish with Tow Cable Connected and Attached ...........................................................3-37

xix
Figure 3-14: Discover 4125 Towfish Control Tab .................................................................................3-41
Figure 3-15: Performing a Rub Test.....................................................................................................3-41
Figure 3-16: Rub Test Screenshot........................................................................................................3-42
Figure 3-17: 4125 Towfish being Deployed .........................................................................................3-44
Figure 3-18: Bottom Track Tab............................................................................................................3-45
Figure 3-19: Tow Vessel Direction vs. Ocean Current ..........................................................................3-47
Figure 5-1: Towfish Parts of Note........................................................................................................5-91
Figure 5-2: Electronics Bottle and Transducer Array Sections Separated .............................................5-91
Figure 5-3: Cables Disconnected from the Electronics Bottle...............................................................5-92
Figure 5-4: Removing the Phillips Head Screws from the Electronics Bottle.........................................5-92
Figure 5-5: Removing the Electronics Chassis from the Electronics Bottle ...........................................5-93
Figure 5-6: Remote Desktop Icon........................................................................................................5-94
Figure 5-7: Remote Desktop Splash Screen.........................................................................................5-95
Figure 5-8: Remote Desktop Warning Screen......................................................................................5-95
Figure 5-9: Closing Sonar.exe..............................................................................................................5-96
Figure 5-10: Tera Term Icon................................................................................................................5-96
Figure 5-11: Tera Term Splash Screen .................................................................................................5-97
Figure 5-12. Terra Term Port Set-up....................................................................................................5-98
Figure 5-13. Motion Sensor Serial Output ...........................................................................................5-98
Figure 5-14. Motion Sensor Calibration Result ....................................................................................5-99
Figure 5-15. Motion Sensor Serial Output ........................................................................................5-100
Figure 5-16: Tilt 0 degrees ................................................................................................................5-100
Figure 5-17: Tilt -90 degrees ............................................................................................................. 5-101
Figure 5-18: Tilt +90 degrees ............................................................................................................ 5-101
Figure 5-19: Compass Calibration Table ............................................................................................ 5-102
Figure 5-20: Declination Information in Terra Term VT ..................................................................... 5-103
Figure 5-21: Using the getDeclination Command in Terra Term VT ................................................... 5-103
Figure 5-22: Magnetic Declination Estimated Value Screen...............................................................5-104
Figure 5-23: Angle of Declination Calculated..................................................................................... 5-105
Figure 5-24: Verifying Declination Angle in Terra Term VT ................................................................ 5-106

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4125i/4125 SIDE SCAN SONAR SYSTEM 0004823_REV_G
LIST OF TABLES
Table 2-1: 4125i-P Topside Processor ...................................................................................................2-8
Table 2-2: 4205i Towfish Specifications ..............................................................................................2-14
Table 3-1: AC Power Cord Wiring........................................................................................................3-24
Table 3-2: 4125i-P Processor Controls and Indicator Lights .................................................................3-27
Table 3-3: 4125i Rackmount Controls and Indicator Lights..................................................................3-27
Table 3-4: Ethernet Devices TCP/IP Addresses ....................................................................................3-30
Table 3-5: Towfish vs. Cable Length Laybacks .....................................................................................3-50
Table 5-1: Topside Processor System Troubleshooting Guide............................................................ 5-107
Table 5-2: 4125i Towfish Troubleshooting Guide .............................................................................. 5-109
Table 5-3: 4125i Portable Spares Kit ................................................................................................. 5-114
Table 5-4: 4125-P (Legacy) Spares Kit................................................................................................ 5-114
Table 5-5: 4125i 400/900 kHz Towfish Spares Kit ..............................................................................5-116
Table 5-6: 4125i 600/1600 kHz Towfish Spares Kit ............................................................................ 5-117
Table 5-7: 4125 Electronics 400-900 kHz Spares Kit .......................................................................... 5-118
Table 5-8: 4125 Electronics 4125 600-1600 kHz Spares Kit ................................................................5-119
Table 5-9: 4125 LT Electronics 400-900 kHz Spares Kit ......................................................................5-120
Table 5-10: 4125 LT Electronics 600-1600 KHZ Spares Kit.................................................................. 5-121

1-1
1.0 OVERVIEW
The EdgeTech 4125 Series (4125i/4125) Dual-frequency Side Scan Sonar System is a portable system
designed for shallow water surveys, detailed object inspection, and search and recovery operations.
Standard system components include a lightweight hydrodynamic towfish that mounts a dual 400/900
kHz or 600/1600 kHz side scan sonar subsystem and is delivered with a portable (4125i-P) or rack-mounted
(4125i-RM) topside processor, a tow cable, and an EdgeTech or user-provided Windows laptop with
EdgeTech’s Discover 4125 Software installed on it. Several specialized options can be ordered with the
system, including a telemetry configuration, longer cables, a depressor wing kit, a magnetometer
interface, a hull-scanning kit, and a keel weight kit.
1.1 4125 Series Applications
Applications for the 4125 Series Dual-frequency Side Scan Sonar System are many, including:
•Hydrographic surveys
•Geological surveys
•Search and recovery
•Channel conditioning/clearance surveys
•Bridge, pier, and harbor wall inspections
•Hull inspections
•Port security
•Archaeological surveys
•SAR (Search and Recovery) Operations
1.2 Main System Components
The 4125 Series Dual-frequency Side Scan Sonar System is composed of a 4125i Towfish, 4125i-P
(Portable) Topside Processor, or 4125i-RM (Rack Mounted) Topside, a tow cable and an EdgeTech or user-
provided computer.
1.2.1 Towfish
The 4125i Towfish contains the sonar transducer arrays and the electronics required to transmit and
receive the sonar signals, to receive the downlink commands from the topside processor, and to provide
the uplink side scan data, sensor data, and status information to the topside processor.
The electronics are contained inside a single, lightweight stainless steel, 200-meter depth-rated housing,
comprising the aft section of the towfish. The forward section is flooded and includes both the port and
starboard transducer arrays. A single O-ring sealed end cap is attached to each end of the housing to seal
it, and the forward end cap contains bulkhead connectors for connecting to the transducer arrays. An